Acoustic Voice Properties of Turkish-Speaking Trans Women Who Have Not Received Gender-Affirming Voice Intervention:...

To compare frequency-related and cepstral-spectral acoustic voice parameters of age-matched cis women and trans women who had not received gender-affirming voice training (GAVT) or voice surgery.

A total of 82 participants, including 41 trans women and 41 age-matched cis women, were included. Sustained vowel phonation (/a/) and connected speech samples were recorded under standardized conditions. Frequency-related acoustic parameters, including mean fundamental frequency (F0), were obtained using the Computerized Speech Lab (CSL) Multi-Dimensional Voice Profile for sustained phonation and Real-Time Pitch software for connected speech. Cepstral-spectral acoustic parameters were obtained using CSL Analysis of Dysphonia in Speech and Voice software. Overall, 13 acoustic parameters related to pitch, intonation, and voice quality were analyzed and compared between groups.

In terms of frequency-related acoustic parameters, cis women demonstrated significantly higher mean F0 across both sustained vowel and connected speech samples, and higher minimum F0, maximum F0, and F0 standard deviation in connected speech samples (P < 0.05). Regarding the cepstral-spectral acoustic parameters, cepstral peak prominence (CPP) and CPP standard deviation were significantly higher in trans women across most speech samples (P < 0.05), whereas no significant between-group differences were observed for the low-to-high spectral ratio. Cepstral-Spectral Index of dysphonia values were higher in cis women for several connected speech samples, although these values remained within normative limits.

The study provides comparative acoustic data for trans women and cis women. Beyond mean F0, between-group differences in pitch variability and cepstral-spectral voice quality measures highlight the importance of comprehensive acoustic evaluation. The inclusion of cepstral-spectral parameters contributes to an underexplored area of the literature and may inform the development of GAVT targets.